My '91 500SEL has the same seats and the handbook tells me to put the seats in the required position first. The press and hold the memory button ( green button ) and then, within 3 seconds, press either button 1 or button 2. Then release both. The seats should now remember this selected position. If you need it, I can scan and e mail you the page from the book. Alternatively, the secret is not to let the wife drive it, as I do ! !